Pharmaceutical and biotechnology companies working to develop coronavirus vaccines are speaking about their progress in Congress.
Many say they are on course to have a vaccine by year's end or early next year.
"I would not wait to see if one is better than another," says Dr. Anthony Fauci, director of National Institute of Allergy and Infectious Diseases.
The nation's top infectious disease expert says Americans should get the vaccine as soon as one becomes available.
How soon that could be was the topic of discussion between lawmakers and pharmaceutical and biotech executives at a hearing on Tuesday.
"We're pursuing two promising vaccines," says Dr. Julie Gerberding, executive vice president and chief patient officer at Merck.
The announcement came as President Donald Trump gave his first coronavirus briefing since April, changing his tone on testing.
"If the doctors and the professionals feel that even though we're at a level that no one would have dreamt possible that they would like to do more, I'm OK with it," says President Trump.
Negotiations have ramped up in recent days on whether to include money for testing in the next round of stimulus, with the White House and Senate Republicans divided on the details of the proposal.
"As it's written right now, I'm not only a no, I'm a hell no," says Sen. Ted Cruz.
This comes amid a shortage of testing supplies and major delays in getting results even though lawmakers estimated that between $7 billion and $8 billion in allocated funding hasn't been spent.
Presumptive Democratic presidential nominee Joe Biden slammed President Trump's handling of the crisis.
"This man simply doesn't understand. You know, he's quit on you and he's quit on this country," says Biden.
The company Astrazeneca says it could have a vaccine ready potentially as early as September.